Demolition construction method for partition diaphragm wall of deep foundation pit

Abstract

The invention provides a demolition construction method for a partition diaphragm wall of a deep foundation pit, which comprises the following steps of: partitioning the diaphragm wall by using a rope saw, forming a certain gradient by cutting a joint in the horizontal direction, transferring a concrete block to a hoisting hole along the gradient by using an electric hoist, hoisting the concrete block to a flat car from the hoisting hole, and discharging the concrete block from the flat car. In the process that the concrete blocks are transferred along the gradient, I-shaped steel and other materials are used for being connected with the underground diaphragm wall which is not dismantled, a guardrail is formed, and it is guaranteed that the concrete blocks do not fall off. The method is high in operability, materials and equipment are simple, the load of the shear wall concrete block does not need to be transmitted to a structural floor, back-jacking measures are reduced, a main body structure can be effectively protected against damage, and the problems that a traditional dismantling method has large influence on the main body structure, dust raising and noise pollution are large, and the construction period is long are solved.

Description

Technical Field

[0001] This invention belongs to the field of building technology, and in particular relates to a construction method for demolishing diaphragm walls separating deep foundation pits. Background Technology

[0002] With urban development and the continuous increase in subway construction mileage, the land value along subway lines has risen, which has also increased the construction difficulty of subway projects. To reduce the impact of foundation pit deformation on subway tunnels during the construction of deep foundation pits, a common method is to use diaphragm walls to divide large foundation pits into smaller ones during the foundation pit design phase. After the basement on one side of the dividing wall is capped and the surrounding area is backfilled, the foundation pit on the other side of the dividing wall is excavated, thereby controlling the overall deformation of the foundation pit and ensuring the safety of the subway tunnel.

[0003] In such projects, the partition walls in the foundation pit need to be demolished layer by layer after the underground structures on both sides are capped and backfilled, thus sealing off the main structure layer by layer. The traditional method involves using excavators to enter the basement and break down the walls, followed by the removal of the debris. This method is noisy, generates significant dust pollution, and has a long demolition period; furthermore, the excavators entering the basement floors may damage the main structural floor slabs. How to solve these problems is a pressing issue that needs to be addressed. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for demolishing diaphragm walls in deep foundation pits, which solves the problems of traditional demolition methods having a significant impact on the main structure, generating large amounts of dust and noise pollution, and having a long construction period.

[0005] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0006] A method for demolishing a diaphragm wall separating a deep foundation pit includes the following steps:

[0007] Step 1: Determine the location and type of truck crane based on the site conditions;

[0008] Step 2: Determine the size of the diaphragm wall sections based on the performance parameters of the truck crane and the location of the lifting port;

[0009] Step 3: Divide the wall into sections according to their size, mark the lines, drill holes, and cut.

[0010] Step 4: Pass the I-beam pin through the lifting hole to fix the I-beam guardrail in place;

[0011] Step 5: Use an electric hoist and wire rope to move the concrete block to be hoisted to the side of the fixed block;

[0012] Step 6: Use a truck crane to lift the concrete blocks out of the basement one by one;

[0013] Step 7: Cut the seam at the bottom of the fixing block and use a truck crane to lift the fixing block out of the basement;

[0014] Step 8: Repeat steps 3 to 7 to dismantle the diaphragm wall layer by layer.

[0015] Furthermore, in step 3, the first concrete block is cut into inverted V-shapes on both sides to facilitate hoisting; the bottom of the fixed block is not cut off, and horizontal cuts are made on both sides of the fixed block to form a certain slope, which slopes towards the fixed block, with a slope of 2%.

[0016] Furthermore, in the demolition process of the deep foundation pit partition diaphragm wall demolition construction, the main structure floor slabs are closed layer by layer according to the design conditions. After the main structure reaches the strength required for the replacement support, the partition diaphragm wall is demolished downwards.

[0017] The present invention has the following beneficial effects:

[0018] This invention uses a wire saw to divide the diaphragm wall into sections, creating a slope in the horizontal cuts. An electric hoist is then used to transfer the concrete blocks along this slope to a hoisting opening, from which they are lifted onto a flatbed truck for removal. During the transfer of the concrete blocks along the slope, I-beams and other materials are used to connect them to the remaining sections of the diaphragm wall, forming a guardrail to prevent the concrete blocks from falling. This method is highly operable, uses simple materials and equipment, and eliminates the need to transfer the load of the shear wall concrete blocks to the structural floor slab, reducing the need for backfilling measures. It also effectively protects the main structure from damage, solving the problems of traditional demolition methods, such as significant impact on the main structure, high dust and noise pollution, and long construction periods. Attached Figure Description

[0019] Figure 1 This is a diagram illustrating the demolition process of the diaphragm wall as described in this invention.

[0020] Figure 2 This is a plan view of the diaphragm wall demolition as described in this invention;

[0021] Figure 3 This is an elevation view of the diaphragm wall demolition as described in this invention;

[0022] In the diagram: 1-Diameter wall; 2-I-beam guardrail; 3-Electric hoist; 4-Wire rope; 5-I-beam pin. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0024] Reference Figure 1 , 2 As shown in Figure 3 (the circled numbers in the figure represent the block numbers of the diaphragm wall), the deep foundation pit separation diaphragm wall demolition construction method of the present invention includes the following process:

[0025] Step 1: Determine the location and type of truck crane based on the site conditions;

[0026] Step 2: Determine the size of section 1 of the diaphragm wall based on the performance parameters of the truck crane and the location of the lifting port;

[0027] Step 3: Divide the concrete into sections according to the size of section 1 of the diaphragm wall, mark the lines, drill holes, and cut. Cut the first concrete block into inverted V-shapes on both sides to facilitate hoisting. Do not cut the bottom of the fixing block. Make horizontal cuts on both sides of the fixing block to form a certain slope, sloping towards the fixing block, with a slope of about 2%.

[0028] Step 4: Pass the I-beam pin 5 through the lifting hole to fix the I-beam guardrail 2 in place;

[0029] Step 5: Use the electric hoist 3 and wire rope 4 to transfer the concrete block to be hoisted to the side of the fixed block;

[0030] Step 6: Use a truck crane to lift the concrete blocks out of the basement one by one;

[0031] Step 7: Cut the seam at the bottom of the fixing block and use a truck crane to lift the fixing block out of the basement;

[0032] Step 8: Repeat steps 3 to 7 to dismantle the diaphragm wall layer by layer.

[0033] In the above demolition process, the main structural floor slabs are sealed layer by layer according to the design requirements. After the main structure reaches the strength required for the replacement support, the intermediate diaphragm wall is demolished downwards.

[0034] The embodiments described above are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for demolishing a diaphragm wall separating a deep foundation pit, characterized in that, The process includes the following: Step 1: Determine the location and type of truck crane based on the site conditions; Step 2: Determine the size of the diaphragm wall (1) blocks based on the performance parameters of the truck crane and the location of the lifting port; Step 3: Divide the wall into sections according to the size of the sections (1), mark the lines, drill holes, and cut. Step 4: Pass the I-beam pin (5) through the hoisting hole to fix the I-beam guardrail (2); Step 5: Use an electric hoist (3) and wire rope (4) to transfer the concrete block to be hoisted to the side of the fixed block; Step 6: Use a truck crane to lift the concrete blocks out of the basement one by one; Step 7: Cut the seam at the bottom of the fixing block and use a truck crane to lift the fixing block out of the basement; Step 8: Repeat steps 3 to 7 to dismantle the diaphragm wall layer by layer.

2. The method for demolishing the diaphragm wall separating a deep foundation pit according to claim 1, characterized in that, In step 3, the first concrete block is cut into an inverted V-shape on both sides to facilitate hoisting; the bottom of the fixed block is not cut off, and horizontal cuts are made on both sides of the fixed block to form a certain slope, which slopes towards the fixed block, with a slope of 2%.

3. The method for demolishing the diaphragm wall separating a deep foundation pit according to claim 1, characterized in that, In the demolition process of the deep foundation pit partition diaphragm wall demolition construction, the main structure floor slabs are closed layer by layer according to the design conditions. After the main structure reaches the strength for replacement support, the partition diaphragm wall is demolished downwards.

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